import 'dart:io';

void main() {
  // ????? ???? ????? ???? ?????
  const int minTemp = 15;
  const int maxTemp = 30;

  // ????? ?????????? ???????
  bool lightsOn = false;
  int thermostat = 20;
  bool securityArmed = false;

  print("Welcome to the Smart Home System!");

  // ???? ?????? ??? ????? ???????? ??????
  while (true) {
    print("\nPlease choose an action:");
    print("1. Toggle lights");
    print("2. Set thermostat temperature");
    print("3. Arm / disarm security system");
    print("4. View system status");
    print("5. Exit");
    stdout.write("Enter your choice: ");
    String? choice = stdin.readLineSync();

    if (choice == null) continue;

    switch (choice) {
      case '1':
        // ????? ???? ???????
        lightsOn = !lightsOn;
        print("Lights are now ${lightsOn ? 'ON' : 'OFF'}.");
        break;

      case '2':
        // ??? ???? ???????
        stdout.write("Set thermostat temperature ($minTemp°C - $maxTemp°C): ");
        String? tempInput = stdin.readLineSync();

        int? newTemp = int.tryParse(tempInput ?? "");

        if (newTemp == null) {
          print("Invalid input! Please enter a number.");
        } else if (newTemp < minTemp || newTemp > maxTemp) {
          print("Temperature must be between $minTemp°C and $maxTemp°C.");
        } else {
          thermostat = newTemp;
          print("Thermostat set to $thermostat°C.");
        }
        break;

      case '3':
        // ????? ???? ?????? ??????
        securityArmed = !securityArmed;
        print("Security system is now ${securityArmed ? 'ARMED' : 'DISARMED'}.");
        break;

      case '4':
        // ??? ???? ?????? ???????
        print("\nSystem Status:");
        print("- Lights: ${lightsOn ? 'ON' : 'OFF'}");

        // ????? ???? FizzBuzz ??? ???? ???????
        if (thermostat % 3 == 0 && thermostat % 5 == 0) {
          print("- Thermostat: $thermostat°C Perfect Day");
        } else if (thermostat % 3 == 0) {
          print("- Thermostat: $thermostat°C Cool Day");
        } else if (thermostat % 5 == 0) {
          print("- Thermostat: $thermostat°C Warm Day");
        } else {
          print("- Thermostat: $thermostat°C");
        }

        // ????? ???? ?????? ?????? ????? ?????
        String securityStatus = securityArmed ? "ARMED" : "DISARMED";
        print("- Security System: $securityStatus");
        break;

      case '5':
        print("Exiting the system. Goodbye!");
        return;

      default:
        print("Invalid choice. Please try again.");
    }
  }
}

/*
 Example Run (Different from the example in the question):

Welcome to the Smart Home System!
Please choose an action:
1. Toggle lights
2. Set thermostat temperature
3. Arm / disarm security system
4. View system status
5. Exit
Enter your choice: 1
Lights are now ON.

Enter your choice: 2
Set thermostat temperature (15°C - 30°C): 18
Thermostat set to 18°C.

Enter your choice: 3
Security system is now ARMED.

Enter your choice: 4
System Status:
- Lights: ON
- Thermostat: 18°C Cool Day
- Security System: ARMED

Enter your choice: 2
Set thermostat temperature (15°C - 30°C): 25
Thermostat set to 25°C.

Enter your choice: 4
System Status:
- Lights: ON
- Thermostat: 25°C Warm Day
- Security System: ARMED

Enter your choice: 5
Exiting the system. Goodbye!
*/